EEB graduate student Chuan Li captured the department’s 2015 – 2016 Outstanding Paper of the Year award for her paper published in the journal Science on the fitness landscape of a tRNA gene.
Li is first author of the paper, published April 14, 2016, with coauthors Wenfeng Qian, a recent EEB alumnus who is currently at the Chinese Academy of Sciences, Calum Maclean, research lab technician, and her advisor, Professor Jianzhi Zhang.
“The graduate student papers published this year were phenomenal and it was really difficult to choose just one,” wrote the review committee, comprised of postdoctoral fellows Andrea Hodgins Davis, Mary Rogalski and Jeet Sukumaran. “In the end, we were most impressed by Chuan Li’s study of the fitness landscape of a tRNA gene in yeast. She was able to design a study that addressed some of the fundamental questions in evolutionary biology. By connecting the genetics to structural changes in a protein to ultimate consequences for fitness so comprehensively, this paper expands the scope of possibility for future work in evolutionary genetics.” Five papers were submitted this year.
“We designed a comparatively easy but powerful methodology for describing fitness landscape,” said Li. “After replacing the original tRNA gene with numerous tRNA variants, I use next generation sequencing to determine the fitness of each variant. I experimentally estimated fitness for over 65,000 yeast tRNA variant under a high-temperature challenge. Overall, I generated and analyzed over 300 gigabytes of sequencing data, which leads to the revelation of a eukaryotic fitness landscape at large scale."
Li ran into some technical obstacles that she solved along the way. For example, she needed to collect over 100,000 yeast colonies and so she had to scale up the transformation experiment. “Moreover, to ensure that only correctly inserted tRNA molecules were sequenced, I designed a simple protocol to amplify the tRNA by two rounds of polymerase chain reaction (PCR).” She liked data analysis best, where she was able to explore more about the fitness landscape, epistasis and their underlying basis.
Each spring, EEB presents this award, worth $500, to a current graduate student. A committee of postdoctoral fellows reviews the papers and selects the most outstanding paper. Congratulations!